Drug and alcohol abusing and dependent delinquents represent a large and greatly underserved population that is at high risk of presenting significant deleterious outcomes and long-term costs for themselves, their families and communities, and society (Belenko &Dembo, 2003). As described by recent reviewers (Belenko &Logan, 2003;Cooper, 2002), juvenile drug courts began emerging in the 1980s to address these problems, and 268 juvenile drug courts were in operation by December, 2003 (Huddleston, Freeman-Wilson, &Boone, 2004). Although juvenile drug courts have continued to proliferate in recent years, evaluation of their capacity to reduce offender substance use and criminal activity has lagged. The proposed study builds on our recent research findings supporting the effectiveness of juvenile drug court and the capacity of evidence-based treatments to enhance juvenile drug court outcomes (Henggeler et al., in press) as well as taking advantage of our extensive experience in the transport of evidence-based practices to community treatment settings. The overriding purpose of this Stage 1-B Treatment Development Study is to develop and test a relatively flexible and low cost strategy for enhancing the outcomes of juvenile drug courts by integrating components of evidence-based treatments into existing substance abuse and drug court services. Specific aims include: Aim 1: Adapt existing intervention and training protocols from evidence-based practices (i.e., contingency management for treating adolescent substance abuse;family engagement strategies from evidence-based treatments of juvenile offenders) for integration into juvenile drug court sites. Aim 2: Conduct a study to examine youth (e.g., substance use and criminal behavior) and system level (e.g., feasibility, implementation fidelity, retention and completion rates, consumer satisfaction, cost estimates) effects of implementing the intervention protocols in six juvenile drug courts. Aim 3: Revise intervention and training protocols in preparation for Stage II study if findings are supportive.